We evaluated the efficacy of eszopiclone (ESZ) and concurrent escitalopram oxalate (EO) in patients with insomnia and co-morbid GAD.

Patients meeting DSM-IV-TR criteria for GAD and insomnia received 10 weeks of EO 10mg and co-therapy with ESZ 3mg or placebo (PBO) for 8 weeks. For the last 2 weeks, ESZ was replaced with single-blind PBO to evaluate discontinuation effects. Sleep, daytime functioning and anxiety measures were captured during the study.

ESZ+EO improved sleep and daytime functioning at each week and the double-blind period average (p<0.05). At Week 8, significantly more ESZ+EO patients had no clinically meaningful insomnia based on ISI</=7. Significant improvements with ESZ+EO (relative to PBO+EO) were observed in HAM-A total scores each week, and Weeks 4-10 excluding the insomnia item. ESZ+EO was significantly better at every timepoint on CGI-I (p<0.02); CGI-S was not different between treatments after Week 1. Median time to anxiolytic response was reduced with ESZ+EO based on HAM-A and CGI-I. HAM-A response and remission rates at Week 8 were higher with ESZ+EO, and HAM-D17 scores were improved at all timepoints (p<0.004). After eszopiclone discontinuation, there was no evidence of rebound insomnia, and no treatment differences in sleep or daytime function. Significant treatment differences in anxiety and mood were maintained after discontinuation.

In this study, ESZ+EO was well tolerated and associated with improved sleep and daytime function without evidence of tolerance. Improvements in anxiety and mood were observed with ESZ+EO.

Support for this study provided by Sepracor Inc., Marlborough, MA.